Biomedical Letters

Advances in Imaging Methods to Detect Vulnerable Plaque: A Review

Muhammad Arif Anwar 1, Zhu Jian1, Angela Yumnam 2, Khawar Ali Shahzad 3, Ma Gen Shan 1*

1 Department of Cardiology, The Affiliated Zhong Da Hospital of Southeast University, No. 87 Dingjiaqiao, Nanjing 210009, China

2 Department of Gastroenterology, The Affiliated Zhong Da Hospital of Southeast University, No. 87 Dingjiaqiao, Nanjing 210009, China

3 Department of Microbiology and Immunology, Southeast University, No. 87 Dingjiaqiao, Nanjing 210009, China.

Abstract

Acute coronary syndromes (ACS) are anticipated to remain the important cause of mortality and morbidity now a days. ACS are mostly caused by plaque rupture. This review paper focuses on the prognostic value of different in vivo determination modalities of vulnerable lesions in coronary artery by OCT, IVUS-VH, intravascular ultrasound (IVUS), intravascular magnetic resonance, Roman and near-infrared spectroscopy, and non-invasive multidetector computed tomography, Positron Emission Tomography (PET) scan, Single Photon Emission Computerized Tomography (SPECT) scan, Magnetic Resonance Imaging (MRI) and their different combinations in patients undergoing coronary angiography. Coronary angiography is considered the standard modality to estimation of the coronary artery disease but the difference in expression of the opacified vascular lumen is too high. By coronary angioscopy, the plaque surface and intraluminal structures can be visualized directly with the utility of intracoronary angioscopy (CAS). The plaque color variation can enlighten plaque complications, such as ulceration, fissures, rupture, intimal breaks and thrombosis with a higher sensitivity than angiography. For intracoronary imaging, IVUS is being used as a "gold standard" which is used to evaluate the positive vessel remodeling. In addition to real-time, high-resolution images of the plaque, but IVUS method is also capable of determining the borders and vessel lumen. Despite amplitude resemblance, the power and frequency of the signal usually vary among different tissues. OCT is found with higher sensitivity, specificity and capacity for description of coronary plaques as compared with other imaging modalities. For identification of fibrous and lipid-rich tissue by measuring differential water diffusion, MR spectroscopy can be used. 18F-FDG PET is normally done for the estimation of myocardial consumption of glucose. SPECT is particularly being used to target high-risk lesions with atherosclerosis. It is concluded that every technique has its own significance and specificity in detection of particular feature of vulnerable plaque. Until now, we are unable to define a single modality in order to detect in vivo vulnerable plaques accurately. A varying combination of above given techniques can help the physicians and medical expertise to increase the predictive value of prognostication. It is highly desired to device such combination of different diagnostic techniques to improve accuracy in early detection of vulnerable plaque.

Keywords: Acute coronary syndromes (ACS), intravascular ultrasound, Magnetic Resonance Imaging (MRI), coronary angiography, prognostication.

Received September 11, 2015 Revised October 14, 2015 Accepted October 25, 2015

*Correspondence: Ma Gen Shan Email: magenshan@hotmail.com Contact: +8613002580569